SHARP(CHINA)INVESTMENT CO.,LTD 
Item Mode Control 
operation 
When resistance is 
low (tempera-ture 
judged higher than 
actual)
Short-circuit When resistance 
is high (tempera-
ture judged lower 
than actual) 
Open-circuit
Compressor 
discharge pipe 
thermistor (TH1) 
Cooling 
Dyring 
Heating 
Expansion valve 
control and 
compressor 
protection 
Compressor operates, 
but room does not 
become cool or warm 
Compressor 
discharge pipe 
temperature 
error indica- 
tion. 
Layer short-circuit or 
open-circuit may 
result in compres-sor 
in normal oper-ation.
Compressor 
discharge pipe 
temperature 
error indica- 
tion. 
Cooling 
Drying 
Outdoor unit heat 
exchanger over 
heat prevention 
Compressor operates at 
low speed or stops. 
Outdoor unit 
thermistor short-
circuit error 
indication. 
Normal operation.  Outdoor  unit 
thermistor 
open-circuit 
error indication.
Heat exchanger 
thermistor (TH2) 
Heating Expansion valve 
control Defrosting 
Defrosting operation is 
not activated as needed, 
and frost accumulates 
on outdoor unit 
Outdoor unit 
thermistor 
short-circuit error 
indication. 
Defrosting operation 
is activated unnece- 
ssarily, and room 
does not become 
warm 
Outdoor unit 
thermistor 
short-circuit 
error indication.
Auto Operation mode 
judgement 
Cooling mode is 
activated even if room 
temperature is low. 
Outdoor unit 
thermistor 
short-circuit error 
indication. 
Heating mode is 
activated even if 
room temperature is 
high. 
Outdoor unit 
thermistor 
open-circuit 
error indication.
Cooling 
Drying 
Operation not 
affected 
Normal operation.  Outdoor  unit 
thermistor short 
-circuit error 
indication. 
Normal operation.  Outdoor  unit 
thermistor open
-circuit error 
indication. 
Outside air 
temper-ature 
thermistor (TH3) 
Heating Rating 
controlDefrosting 
Defrosting operation is 
activated unnecessarily.
Outdoor unit 
ther-mistor short
-circuit error 
indication. 
Defrosting operation 
is not activated, and 
frost accumulates on 
outdoor unit. 
Outdoor unit 
thermistor 
open-circuit 
error indication.
 
[3] THERMISTOR TEMPERATURE CHARACTERISTICS 
1. Indoor unit and outdoor exchange temperature and outside air temperature thermistor temperature characteristics 
 
TEMP. 
Resistance 
(k Ohm) 
Votalge of 
resisitance TEMP. 
Resistance 
 (k Ohm) 
Votalge of 
resisitance TEMP. 
Votalge of 
resisitance 
-30 63.513  4.628 15  7.447  2.968 60 1.464  1.115 
-29 60.135  4.609 16  7.148  2.918 61 1.418  1.088 
-28 56.956  4.589 17  6.863  2.868 62 1.374  1.061 
-27 53.963  4.568 18  6.591  2.819 63 1.331  1.035 
-26 51.144  4.547 19  6.332  2.769 64 1.290  1.009 
-25 48.488  4.524 20  6.084  2.720 65 1.250  0.984 
-24 45.985  4.501 21  5.847  2.671 66 1.212  0.960 
-23 43.627  4.477 22  5.621  2.621 67 1.175  0.936 
-22 41.403  4.452 23  5.404  2.572 68 1.139  0.913 
-21 39.305  4.426 24  5.198  2.524 69 1.105  0.890 
-20 37.326  4.399 25  5.000  2.475 70 1.072  0.868 
-19 35.458  4.371 26  4.811  2.427 71 1.040  0.847 
-18 33.695  4.343 27  4.630  2.379 72 1.009  0.825 
-17 32.030  4.313 28  4.457  2.332 73 0.979  0.805 
-16 30.458  4.283 29  4.292  2.285 74 0.950  0.785 
-15 28.972  4.252 30  4.133  2.238 75 0.922  0.765 
-14 27.567  4.219 31  3.981  2.192 76 0.895  0.746 
-13 26.239  4.186 32 
3.836 
2.146 77 0.869  0.728 
3-3 
Resistance
(k Ohm)